Further to Lebro post of his cylinder pressures I pose this question.   Bob. What CR did you aim at with your engine? my old collected notes shew this relationship between cr and psi 140 psi~8:1 150 psi~8.5:1 160 psi~9:1 170 psi~9.5:1 180 psi~10:1 190 psi~10.5:1 Please feel free to rubbish this info.    Does cam timing and tappet clearance affect the cylinder pressure? My own engine measures 180-185 psi wot. cranking speed. The build measurements and